Cellulose-ether solvent and composition



' Patented Jan. 2, 1923.

isos'ra'rss PATENT OFFICE.

STEWART J. .GARBOLLyOF ROCHESTER, NEW YORKQASSIGNOR TO EASTMAN KODAK COMPANY, OF ROCHESTER, NEW YORK, A CORPORATION OE NEW YORK.

CELLULOSE-ETHER SOLVENT AND COMPOSITION.

No Drawing.

T a n-lm'nz. may concern:

Be it known that I. STEWART J. CARROLL a citizen of the. United States of America. residing at Rochester, in the county of Mon- .5 roe and State of New York, have invented certain new and useful Improvements in (.elluloSe-Ether Solvents and Compositions.

of which the following is a full. cleaig andexact specification.

This invention relates to solvents for ma king strong Solutions of cellulose ether and also relates to the cellulose ether compositlons. produced by the aid of such solvents. ()ne object of my invention is to provide a solvent which will dissolve such large proportions of cellulose ethers that thick or viscous fiowable solutions may be obtained for use in plastic and film making arts. Another object of my invention is to provide ace'llulose ether solution which may be manufactured into strong. flexible. transparent film on the machines and by the. methods now in use.

In U. S. Patent No. 1.188.376. Lilienleld. June 20. 1916. there are disclosed a series of alkyl ethers of cellulose. Certain of these are practically insoluble' in water, and my invention relates but is not-limited to the ethers having that property. While the others form thin solutions in methyl alcohol or toluene, it has been found that such Single solvents by themselves do not dissolve a sufficient proportion of the ethers to makea desirable thick flowable, composition or dope, such as may be used in the manufacture of photographic film base by the customary methods, or in the other plastic arts.

1 have discovered that an adequately strong and useful solvent may be prepared 40 by mixing these substances. VVhi le the pro- Aiiplication filed April 5, E1921. Serial No. 458,738.

part additional suppleness or incombustibiL ity. orother qualities. to the film may then be added to the dope. such modifying agents being. for example. triphenyl or tr'icresvl phosphate, camphor. etc. U

The ingredients are of the ordinarv commercial type and sufficiently purified for the process of film manufacture. so as to give a dope yielding films having the proper relative freedom from color. The viscous-flowable dope above described can be used in connection with the usual filn'i-forming apparatus without the necessity of expensive alterations in the latter.

Some of the toluene may remain in the film or other product and impart additional flexibility to it, the alcohol passing out more rapidly than the hydrocarbon during the setting and curing of the film.

Having thus described my invention. what I claim as new and desire to secure by Letters Patent is:

1. A compound solvent for alkyl ethers of cellulose. comprising a mixture of methyl alcohol and toluene.

2. A compound solvent for alkyl ethers of cellulose. comprising from 51) to parts by weight of methyl alcohol and to parts by weight of toluene.

3. A viscous fiowable film-forming composition. comprising an alkyl ether of cellulose dissolved in a mixture of methyl alcohol and toluene.

4;. A viscous flowable film-forming oomposition, comprising an alkyl ether of cellulose dissolved in a compound solvent containing from 50 to 25 parts by weight of methyl alcohol and 50 to 7.) parts of toluene.

5. A composition of matter. comprising water-insoluble ethyl cellulose dissolved in a mixture of methyl alcohol and toluene.

6. A composition otmatter. comprising a solution of 1 part by weight of water-insoluble ethyl cellulose in substantially 5 parts of a mixture containing methyl alcohol and toluene.

Signed at Rochester, New York, this 30th day of March, 1921.

STEWART J. CARRO. 

